Graphene is a one-atom-thick planar sheet of sp2-bonded carbon atoms that are densely packed in a honeycomb lattice, It is considered to be the basic unit to construct other dimension SP2 carbon materials. The unique structure of graphene enabled a large specific surface, good electrical conductivity and excellent chemical stability, which has aroused extensive research. It is easy for graphene sheets to agglomerate because of the π-π interactions. Therefore, it is very meaningful to construct three-dimensional graphene macroscopic material with single graphene. In 2010, Gaoquan Shi and others first prepared graphene hydrogel by hydrothermal method (ACS Nano, 2010, 4, 4324-4330). It is worth noting that the mechanical properties of pure graphene hydrogels are poor, which can't meet the requirements of practical applications. Therefore, it is important to improve the physical and mechanical properties of the hydrogel.
Phytic acid is a kind of green environmental protection organic acid which exists widely in nature, easy to form a stable structure between molecules, and whose six membered ring structure has good stability, good electrical conductivity and strong complexing ability. The invention adopted the hydrothermal method, which was used as a coupling agent between the graphene sheets, can avoid irreversible aggregation of graphene, enhanced mechanical properties of graphene hydrogels, but can also improve the conductivity of graphene hydrogels because of the phytic acid's good conductivity.